The Study On Sap Flow Of Main Arbor Species In Taiyue Mountain In Shanxi Province

By using ICT-2000TE(Transpiration-Environment) through TDM(Thermal Dissipation Method), the stem sap flow dynamics of main arbor species (Quercus Liaotong, pinus tabulaeformos, Populus davidiana, Betula platyphylla, Larix Principis-rupprechti and Juglans mandshuria) in field under the consistent tree status and environmental factors was studied. The tree biological and environmental factors influencing the diurnal and seasonal stem sap flow were discussed, and mathematical models on the responses of the diurnal sap flow to the related environmental factors (solar radiation, air temperature, air relative humidity, soil temperature, soil moisture, wind speed )were developed during the growing season.Diurnal course of each tree stem sap flow density exhibited mostly mono-peak patterns during clear sky days in the growing season, except that in the beginning of frondescence of Quercus Liaotong showed irregular diurnal course. Maximum values and their corresponding time were different in terms and species, which were influenced by species characters and environmental factors.The use of water in growing season of model trees was calculated on the basis of sap flow density, and the ability of water consuming were compared with each other. The order of water-consuming ability is Populus davidiana, Juglans mandshuria, Larix Principis-rupprechti, Betula platyphylla, pinus tabulaeformos, and Quercus Liaotong.The originality of the paper is for the first time that the thermal dissipation was applied to study stem sap flow of main arbor species on Taiyue Mountain in Shanxi province and the condition of sap flow on this field was more accurately measured. This is very useful for further understanding of physiological and ecological character of these species. It also provides scientific basis for forestation on some aspects, such as the select of adaptive water-saving species and application of water-saving measures.